Such a mounting device is conventionally provided in a processing apparatus for performing a predetermined process on a target object (e.g., a semiconductor wafer). A representative processing apparatus includes an inspection apparatus such as a probe apparatus or the like. As illustrated in, e.g., FIG. 6A, the inspection apparatus includes: a mounting device 1 for mounting thereon a semiconductor wafer W so that the semiconductor wafer W can be lifted up and down; a stage mechanism 2 on which the mounting device 1 is provided, for moving the mounting device 1 in a horizontal (X and Y) direction; a probe card 3 disposed above the mounting device 1; and an alignment mechanism (not shown) for performing alignment between a plurality of probes 3A of the probe card 3 and electrode pads of the semiconductor wafer W. Further, the inspection apparatus is constructed to inspect the semiconductor wafer W by making electrical contact between the semiconductor wafer W and the probes 3 after performing the alignment between the probes 3A and the electrode pads of the semiconductor wafer W by the alignment mechanism.
As shown in FIG. 6A, the stage mechanism 2 includes an X stage 2A, a Y stage 2B and a fixed stage 2C. The X stage 2A and the Y stage 2B move the mounting device 1 in the X and Y directions by respective driving units (not shown). An X guide mechanism 2D is interposed between the X stage 2A and the Y stage 2B, so that the X stage 2A moves on the Y stage 2B in the X direction along the X guide mechanism 2D. A Y guide mechanism 2E is interposed between the Y stage 2B and the fixed stage 2C, so that the Y stage 2B moves on the fixed stage 2C in the Y direction along the Y guide mechanism 2E.
Further, as depicted in FIGS. 6A and 6B, the mounting device 1 includes: a mounting table 1A for mounting thereon a semiconductor wafer W; an elevation body 1B connected to a central portion of a bottom surface of the mounting table 1A; and a pair of right and left support members 1C supporting the elevation body 1B at right and left sides thereof so that the elevation body 1B can be lifted up and down. The mounting device 1 vertically moves the elevation body 1B and the mounting table 1A by an elevation driving mechanism installed inside the elevation body 1B. The elevation body 1B is a housing having a top portion of square shape, and accommodates therein the elevation driving mechanism. The elevation body 1B has a size such that the four corners thereof are disposed near the periphery of the mounting table 1A.
As illustrated in FIG. 6B, each of the right and left support members 1C is an angle bracket having a vertical plate 1D and a horizontal plate 1E perpendicular to the vertical plate 1D at an approximately middle portion thereof, and is fixed on the X stage 2A by bolts (not shown) fitted into the X stage 2A through a plurality of bolt holes 1F of the horizontal plate 1E. A plurality of brackets 1G spaced from each other in a width direction are provided between the vertical plate 1D and the horizontal plate 1E. The vertical plates 1D are extended to penetrate through a hole of the X stage 2A, and lower portions of the vertical plates 1D are connected with each other below the X stage 2A by a connecting plate 1H. A motor 1I forming an elevation driving mechanism is installed at a central portion of the connecting plate 1H. The elevation driving mechanism includes: the motor 1I; a screw (not shown) coupled to the motor 1I; and a nut member (not shown) engaged with the screw and fixed to the elevation body 1B. The vertical plate 1D is formed to have a width substantially same as that of a surface of the elevation body 1B facing the vertical plate 1D.
Two elevation guide rails 1J are fixed to the vertical plate 1D of each of the support members 1C while being spaced from each other at a predetermined interval in the width direction. Each of the elevation guide rails 1J is engaged with vertical engaging bodies 1K fixed to the elevation body 1B.
However, the conventional mounting device 1 is disadvantageous in that a speed of movement by the stage mechanism 2 is restricted due to a heavy weight of the elevation body 1B and the support members 1C, and also in that time is required until the mounting table 1 stops its movement and becomes stabilized due to poor vibration characteristics and a remaining vibration after the movement. Moreover, a weight balance is poor because a weight distribution in the X direction is different from that in the Y direction. Further, the engaging bodies 1K are attached to the elevation body 1B and extended vertically while being spaced from each other at predetermined intervals, so that a rigidity of the elevation body 1B with respect to a probe pressure applied to the mounting table 1A from the probe 3A is not high enough considering its weight. Besides, since the elevation body 1B is supported by the support members 1C only at right and left sides thereof, the rigidity is not even in all directions thereof. Accordingly, an inclination of the mounting table 11 varies depending on the location to which the probe pressure is applied.